Figure coordinate marking apparatus

Abstract: A figure coordinate marking apparatus having a fine movement device capable of easily and accurately adjusting the marker to a specific coordinate position of a figure and a marker capable of clearly indicating a marking point. The figure coordinate marking apparatus comprises a main body having rollers provided at each end of a straight horizontal axle perpendicular to a running direction thereof so that the main body can run in only the straight running direction, a display device, an input device, and calculating means. A measuring lever is pivotably supported on the main body to rotate right or left relative to the running direction on a horizontal plane. A first wheel for fine movement in the substantial running direction of the main body, and a second wheel for fine movement in a turning direction of the measuring lever are provided. The first wheel and second wheel are normally kept a small distance above a sheet of paper on which a figure to be measured is drawn, by an elastic member.

Description: 1. Field of the invention The present invention relates to a figure coordinate marking apparatus for marking a specific coordinate position, such as a centroid of a plane figure onto the plane figure by tracing along a contour of the plane figure. 2.Background information In a prior figure coordinate marking apparatus known from EP-A-400 536, a specific coordinate position, such as a known centroid etc. of a known figure is entered though an input device in tile main body of the figure coordinate marking apparatus. An internal calculating device in the figure coordinate marking apparatus calculates the deviation of coordinates of a marker provided adjacent to a tracing point by a tracing portion of a measuring lever on the figure coordinate marking apparatus, from the coordinates of the figure entered representing the specific coordinates position. The display device of the figure coordinate marking apparatus displays the deviation. The measuring lever is then moved so that the deviation of the coordinates of the marker from the coordinate of the figure entered representing the specific coordinates position becomes zero on the display, and the marker moved with the measuring lever then marks the specific coordinate position of the figure on the figure. However, if a precise drawing is required, the prior figure coordinate marking apparatus requires very high skill to accurately adjust the marker to the specific coordinate position of the figure, often resulting in error to a great degree. Also, the prior art has the disadvantage that indication of the marking point is often unclear even if the marker is accurately adjusted to the specific coordinate position of the figure. Summary of the invention With a view to solve the foregoing problems of the prior art, it is an object of the present invention to provide a figure coordinate marking apparatus which comprises a fine moving means capable of easily and accurately adjusting a marker on the figure coordinate marking apparatus to a specific coordinate position of a figure with a marker capable of clearly marking a point. A figure coordinate marking apparatus according to the present invention is comprised of a main body having rollers provided at each end of a horizontal axle perpendicular to the running direction thereof so that the main body can run in only a straight running direction, a display device, an input device, and calculating means. The apparatus further comprises a measuring lever pivotably supported on the main body to rotate right or left relative to the running direction in a horizontal plane. The measuring lever has a marker and a tracing portion for tracking a figure to be measured to obtain coordinates, area, length or the like from a figure, from which the calculating means calculates a specific coordinate position of the figure. The display device indicates any difference between the specific coordinate position of the figure and a coordinate position of the marker, and the tracing portion is moved to reduce the difference to zero. The figure coordinate marking apparatus further has a first wheel for fine movement in a running direction of the main body and a second wheel for fine movement in a turning direction of the measuring lever. The first wheel and the second wheel normally maintains a small distance above a sheet of paper on which the figure is drawn, by an elastic member. The first wheel can be rotatably supported at an end of the measuring lever by a horizontal axle perpendicular to a straight line connecting a supporting fulcrum of the measuring lever with a tracing point of the tracing portion. Otherwise, the first wheel can be supported at a center portion of the measuring lever, the horizontal axle of the first wheel being kept in parallel with the horizontal axle of the rollers. The horizontal axle of the first wheel may be kept in parallel with the rollers by a link arrangement of a belt extending between the first wheel and a supporting fulcrum for the measuring lever. Otherwise, the horizontal axle of the first wheel may be kept in parallel with the rollers by a link arrangement of bars extending between the first wheel and a supporting fulcrum for the measuring lever. The second wheel may be rotatably supported by a horizontal axle directed toward a supporting fulcrum for the measuring lever. The marker can comprise a center needle for pressing a sheet of paper and a rotating member rotatably supported on the marker for holding a pencil lead to draw a small circle around the center needle. As described above, the measuring lever of the figure coordinate marking apparatus of the present invention moves near to the specific coordinate position of the figure in a manner similar to the prior art. In a final fine movement area, the first and second wheels rotate while pressed onto the paper against the elasticity of the elastic member holding them. This easily and accurately allows make the marker fine movement to the specific coordinate position of the figure. After the marker is pointed at the specific coordinate position of the figure, the center needle of the marker is pressed on the paper and the rotating member holding the pencil lead rotates a turn. This draws a small circle around the center needle with the center needle being at the center, thereby allowing the marked point to be easily confirmed after drawing. It should be noted that after drawing and confirming, the small circle drawn by the pencil lead can be erased with an eraser to get rid of excess marks on the figure. Embodiments of the invention will become more apparent from the following portion of this specification and from the accompanying drawings. Brief description of the drawings In the drawings: Fig. 1 is a plan view of a first embodiment of a figure coordinate marking apparatus according to the present invention; Fig. 2 is a longitudinal side view of the first embodiment; Fig. 3 is an end view of the first embodiment; Fig. 4 is a rear view of the first embodiment; Fig. 5 is a plan view of a second embodiment of the figure coordinate marking apparatus according to the present invention; Fig. 6 is a longitudinal side view of the second embodiment; Fig. 7 is an end view of the second embodiment; Fig. 8 is a rear view of the second embodiment having a belt link arrangement; Fig. 9 is a rear view of a part of the second embodiment having a link arrangement of bars. Detailed description of the invention The following describes a first embodiment of the present invention by reference to the accompanying drawings. The figure coordinate marking apparatus is comprised of main body 1 having display device 11, input device 12, internal calculating device (not shown), rollers 13 rotatably supported on a side of main body 1 at each end of a straight horizontal axle perpendicular to a running direction of main body 1 so that main body 1 can run only in the running direction. The figure coordinate marking apparatus also comprises measuring lever 2 supported at fulcrum 14 on main body 1 so as to be turnable right and left relative to the running direction of main body 1. Measuring lever 2 has tracing portion 21 at the end thereof. First wheel 22 for fine movement of the whole apparatus including main body 1 and measuring lever 2, in the running direction of main body 1, and second wheel 23 for fine movement of measuring lever 2 in the turning direction of measuring lever 2 are respectively supported at the end of measuring lever 2. Both first wheel 22 and second wheel 23 are held by elastic member 24 (Fig. 4) such as, a plate spring or the like on a rear side of measuring lever 2 to maintain a small distance above a sheet of paper on which a figure is being drawn. A horizontal axle of first wheel 22 is held at right angles to a straight line connecting supporting fulcrum 14 of main body 1 with tracing point 211 of tracing portion 21 of measuring lever 2. A horizontal axle of second wheel 23 is held directly in line with supporting fulcrum 14. Further, measuring lever 2 has marker 25 supported at the end thereof. Marker 25 is comprised of a center needle for pressing on a sheet of paper and a rotating member rotatably connected to and supported on the marker for holding a pencil lead for drawing a small circle around the center needle. Any difference between the coordinate positions of marker 25 and tracing point 211 are stored as data in a calculating device (not shown). The calculating device calculates a specific coordinate position of a figure to be measured and also a difference between the specific coordinate position of the figure and a coordinate position of marker 25 using the above data stored in the calculating device as an offset. Display device 11 displays the specific coordinate position and the difference to show a point where marker 25 should be positioned. In turn, the following describes the operation of the figure coordinate marking apparatus. Input device 12 is used to enter calculation commands for calculating specific coordinate positions of the figure, such as a centroid of the figure. After that, tracing point 211 is moved along the contour of the figure to obtain and store X and Y coordinates of minutely sectioned positions of the contour of the figure in the calculating device. As the figure is sectioned minutely enough, it performs a continuous measurement. If the figure to be measured is defined by a plurality of straight lines, a representation of the figure is entered before measurement. The tracing point is then moved to vertexes of the figure defined by straight lines, coordinates of which are read when a coordinate read button is pressed. Tracing along the contour of the figure between the vertexes can be omitted on the way from a vertex to a next vertex. A continuous measurement selector button 212 provided at the end of measuring lever 2 is used to select each representative measurement of the figure or the continuous measurement of figure. If a figure to be measured is defined by a plurality of straight lines, coordinate read button 213 is pressed at vertex positions of the figure, thereby entering the coordinates of the vertexes into the calculating device. After the coordinates along the contours or all the vertexes of the figure are read, display device 11 displays the necessary data. The necessary data are the specific coordinates of, for example, the centroid of the figure and the coordinates of a current marker position and a difference between the specific coordinates and the coordinates of the marker. Measuring lever 2 is moved until the difference is zero so that a position of the marker goes to the specific coordinate position. In this case, as it is difficult to precisely move marker 25 to a specific coordinate position, first wheel 22 or second wheel 23 is utilized to accurately move the marker near the specific coordinate position. Though the first and second wheels 22, 23 are normally kept a small distance above the sheet of paper on which a figure is being drawn by elastic member 24, they can be pressed toward the paper and rotated on it so that the marker can be easily and accurately moved to coincide with the specific coordinate position. Fig. 5 is a plan view of a second embodiment of the figure coordinate marking apparatus according to the present invention, Fig. 6 is a longitudinal side view of the second embodiment, Fig. 7 is an end view of the second embodiment, and Fig. 8 is a rear view of the second embodiment. The figure coordinate marking apparatus comprises main body 1 having display device 11, input device 12, internal calculating device (not shown), rollers 13 rotatably supported on a side of main body 1 at each end of a straight horizontal axle perpendicular to a running direction of main body 1 so that main body 1 can run only in the running direction. The figure coordinate marking apparatus also comprises measuring lever 3 supported by fulcrum 14 on main body 1 so as to be turnable right and left relative to the running direction of main body 1. Measuring lever 3 has tracing portion 31 at the end thereof. Measuring lever 3 also has second wheel 33 for fine movement of measuring lever 3 in the turning direction of measuring lever 3. Second wheel 33 is held by elastic member 34 such as a plate spring or the like disposed on a rear side of measuring lever 3 to maintain a small distance above the sheet of paper on which a figure is being drawn. First wheel 32 is supported at a center of measuring lever 3 for fine movement of the whole apparatus including main body 1 and measuring lever 3, in the running direction of main body 1. Further, fixed wheel 141 (Fig. 8) is fixed to supporting fulcrum 14 and slave wheel 142 having the same diameter as fixed wheel 141 is fixed to a horizontal axle of first wheel 32 for rotating the horizontal axle of first wheel 32 around a vertical axle on a horizontal plane. Unslidable belt 35 which is for example a timing belt or the like extending between fixed wheel 141 and slave wheel 142 constitutes a link arrangement. It should be noted that slave wheel 142 and first wheel 32 are normally kept a small distance above a sheet of paper on which a figure to be measured is drawn by an elastic member (not shown), as in the first embodiment described above. Fig. 9 is a rear view of another link arrangement comprised of two bars 36 in place of the link arrangement of belt 35 of Fig. 8. Both ends of each of two bars 36 are turnably held in place. Namely one end of each bar 36 is turnably attached to main body 1 while the other end of each bar 36 is turnably attached to a disk fixed the horizontal axle of first wheel 32. Distances between fulcrums of the both ends of two bars 36 are set equal so that the horizontal axle of first wheel 32 and an axle of roller 13 of main body 1 can be kept parallel irrespective of the turning angle of measuring lever 3. As other arrangements are the same as in the first embodiment, detailed description of them is omitted here. Operation of the second embodiment is identical with the operation of corresponding parts in the first embodiment except for first wheel 32. As described above, the horizontal axle of first wheel 32 and the axle of roller 13 of main body 1 can be kept parallel irrespective of the turning angle of measuring lever 3, therefore when first wheel 32 is pressed to move on a sheet of paper to be drawn, a moving direction of measuring lever 3 can coincide with the direction of movement of roller 13, while being independent from a turning angle of measuring lever 3. As described so far, the figure coordinate marking apparatus of the present invention can calculate a specific coordinate position of a figure to be measured, such as the centroid on the figure, by means of the calculating device. The apparatus also displays a difference of a current position of the marker from the specific coordinate position of the figure. The measuring lever is moved until the difference is zero. In that case, if the difference approaches zero, the first and second wheels are used for fine movement of the measuring lever so that the marker can easily and accurately come to the specific coordinate position of the figure. The marker that is of the so-called compass type can clearly point the position to be marked by the position of the center needle and a small circle drawn around the center needle with the pencil lead. The small circle can be erased with an eraser when it is not needed.

Claims: A figure coordinate marking apparatus comprising a main body (1) having rollers (13) each of which is provided at each end of a horizontal axle perpendicular to a running direction thereof so that the main body can run in only the straight running direction, a display device (11), an input device (12), and calculating means, a measuring lever (2,3) pivotably supported on the main body rotatable right or left relative to the running direction on a horizontal plane, said measuring lever having a marker (25) and a tracing portion (21,31) tracing a figure to be measured to obtain coordinates, area, length or the like for said figure, said calculating means calculating a specific coordinate position of said figure, and said display device indicating a difference between the specific coordinate position of the figure and a coordinate position of said marker, characterized by a first wheel (22,32) fine movement of said measuring lever (2,3) substantially in the running direction of the main body (1), a second wheel (23,33) for fine movement of said measuring lever in a turning direction of the measuring lever, spacing means to normally maintain said first and second wheels a small distance above a sheet of paper on which the figure is drawn; said spacing means allowing said first and second wheels to be pressed down on said sheet of paper for fine adjustment. The figure coordinate marking apparatus according to claim 1, wherein the first wheel (22) is rotatably supported at an end of the measuring lever (2) by a horizontal axle perpendicular to a straight line connecting a supporting fulcrum (14) for the measuring lever with a tracing point (211) of the tracing portion (21). The figure coordinate marking apparatus according to claim 1, wherein the first wheel (32) is rotatably supported at a center portion of the measuring lever (3), and including means (35,36) for keeping the horizontal axle of the first wheel parallel to said rollers (13). The figure coordinate marking apparatus according to claim 3, wherein said means for keeping the horizontal axle of said first wheel (32) parallel to said rollers (13) comprises a belt link (35) arrangement extending between said first wheel axle and said measuring lever (3) supporting fulcrum (14). The figure coordinate marking apparatus according to claim 3, wherein said means for keeping the horizontal axle of said first wheel parallel to said rollers comprises a link arrangement of bars (36) extending between the first wheel axle and said measuring lever (3) supporting fulcrum (14). The figure coordinate marking apparatus according to claim 1, wherein the second wheel (23,33) is rotatably supported by a horizontal axle directly in line with a supporting fulcrum (14) for the measuring lever (3). The figure coordinate marking apparatus according to claim 1, wherein the marker (25) comprises a center needle for pressing on a sheet of paper and a rotating member rotatably supported on the marker for holding a pencil lead for drawing a small circle around the center needle positioned at a center of the small circle. The figure coordinate marking apparatus according to claim 1, includes means for keeping the horizontal axle of said first wheel parallel to said rollers, said means for keeping the first wheel axle parallel to said rollers comprises a linking arrangement extending between said first wheel axle and a fulcrum on said main body supporting said measuring lever. The figure coordinate marking apparatus according to claim 8, in which said linking arrangement comprises a belt linking arrangement. The figure coordinate marking apparatus according to claim 8, in which said linking arrangement is a linking arrangement of bars.

Inventors: KUBO AKIO, KUBO, AKIO
Applicants: KUBO AKIO, KUBO, AKIO
Application year: 1994
Main classification: G01B5
IPC codes: G01B5, B43L13, G06T7